The present invention is directed to techniques and apparatus for reducing the toggle and/or misalignment of a fracture fixed with an intramedullary device as it is loaded. More specifically, but not exclusively, the present invention relates generally to a bioresorable intramedullary canal diameter reducer adapted to be placed within a specific point within the intramedullary canal. While the present invention was developed for reducing the intramedullary canal diameter at a specific point, certain applications may be in other areas.
With reference to FIG. 1, there is illustrated an example of a fracture repair wherein the diameter of a portion of the intramedullary canal is greater than the largest intramedullary rod or nail that can fit within the bone. As can be observed in FIG. 1, the diameter of the canal can vary over it's length and as a result of this difference in diameter the fracture fragments can “toggle” or become misaligned due to “shear” as the fracture is loaded.
One embodiment of the present invention might include a canal diameter reducer adapted to be placed within an intramedullary canal comprising a block of material having a shape, size and dimensions appropriate for being located within the intramedullary canal alongside an intramedullary member. The term intramedullary member is used herein to include intramedullary rods and intramedullary nails. The block stabilizes the intramedullary member and prevents toggling and/or misalignment due to shear.
Another embodiment of the invention is a canal diameter reducer adapted to be placed within an intramedullary canal and involving an elongated block having a concave inner surface extending longitudinally of the block. The block is adapted to be placed in the canal between an intramedullary member and the wall of the canal to prevent toggling and misalignment due to shear. The block is adapted to contact the intramedullary member with the concave inner surface of the block.
Still another embodiment of the invention involves a canal diameter reducer including a block having a convex outer surface which is provided with a series of projections for engagement with the bone to prevent movement relative to the bone. The block is adapted to be placed in the intramedullary canal between an intramedullary member and the wall of the canal with the series of projections in engagement with the wall of the canal. The block is adapted to engage the intramedullary member to prevent toggling and misalignment due to shear.
Still a further embodiment of the invention is a canal diameter reducer having tapered ends and a longitudinally extending aperture sized for reception of a guide wire. The block also has at least one hole therethrough for attachment of a suture. The block is adapted to be placed in the intramedullary canal between the intramedullary member and the wall of the canal to prevent toggling and misalignment due to shear.
Still a further embodiment of the invention is a canal diameter reducer having tapered ends and a concave inner surface extending longitudinally of the block. The block also has a convex outer surface. The tapered ends extend from the convex outer surface to the concave inner surface and taper in such a manner as to cause the outer surface to extend longitudinally a greater distance than the inner surface. The block is adapted to be placed in the intramedullary canal between an intramedullary member and the wall of the canal to prevent toggling and misalignment due to shear. The block contacts the intramedullary member with the concave inner surface.
Still another embodiment of the invention is a canal diameter reducer adapted to be placed within an intramedullary canal comprising an elongated block having a concave inner surface extending longitudinally of the block. The block has a convex outer surface which is provided with a series of projections for engagement with the bone to prevent movement relative to the bone. The block has tapered ends which extend from the convex outer surface to the concave inner surface and taper in such a manner as to cause the outer surface to extend longitudinally a greater distance than the inner surface. The block has a longitudinally extending aperture sized for reception of a guide wire and also has at least one hole therethrough for attachment of a suture. The block is adapted to be placed in the intramedullary canal with the concave inner surface in contact with an intramedullary member to prevent toggling and/or misalignment due to shear.
Still another embodiment of the invention is a process for reducing the toggle and misalignment of a fracture fixed with an intramedullary member. The process comprises forming an entry opening in the fractured bone in the end of the bone leading into the intramedullary canal. A further step is inserting a block through the entry opening into the intramedullary canal to reduce the diameter of the intramedullary canal. Finally an intramedullary member is inserted through the opening into the intramedullary canal to a position alongside the block.
One object of the present invention is to provide a unique intramedullary canal diameter reducer.
Further, forms, objects, features, aspects, benefits, advantages and embodiments of the present invention shall become apparent from the description and drawings provided herewith.